Django : ProgrammingError: column "id" does not exist

Question

I try to use postgresql database (before I had SQLite) but I have a message when I execute python manage.py migrate :

Operations to perform:
Apply all migrations: sessions, admin, sites, auth, contenttypes, main_app
Running migrations:
Rendering model states... DONE
Applying main_app.0004_auto_20161002_0034...Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 353, in execute_from_command_line
utility.execute()
File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 345, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 348, in run_from_argv
self.execute(*args, **cmd_options)
File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 399, in execute
output = self.handle(*args, **options)
File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/migrate.py", line 200, in handle
executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/executor.py", line 92, in migrate
self._migrate_all_forwards(plan, full_plan, fake=fake, fake_initial=fake_initial)
File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/executor.py", line 121, in _migrate_all_forwards
state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/executor.py", line 198, in apply_migration
state = migration.apply(state, schema_editor)
File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/migration.py", line 123, in apply
operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/operations/fields.py", line 201, in database_forwards
schema_editor.alter_field(from_model, from_field, to_field)
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/base/schema.py", line 482, in alter_field
old_db_params, new_db_params, strict)
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/postgresql/schema.py", line 110, in _alter_field
new_db_params, strict,
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/base/schema.py", line 634, in _alter_field
params,
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/base/schema.py", line 110, in execute
cursor.execute(sql, params)
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/utils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "/usr/local/lib/python2.7/dist-packages/django/db/utils.py", line 95, in __exit__
six.reraise(dj_exc_type, dj_exc_value, traceback)
File "/usr/local/lib/python2.7/dist-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: column "id" does not exist
LINE 1: ..._app_projet" ALTER COLUMN "id" TYPE integer USING "id"::inte...

So I guess this error is about my model 'Projet' but this model has ID field ! I see that in 0001_initial.py :

...
migrations.CreateModel(
        name='Projet',
        fields=[
            ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
            ('name', models.CharField(db_index=True, max_length=30)),
            ('presentation', models.TextField(max_length=2500, null=True)),
...

My migration main_app.0004_auto_20161002_0034 :

class Migration(migrations.Migration):

    dependencies = [
        ('main_app', '0003_auto_20161002_0033'),
    ]

    operations = [
        migrations.AlterField(
            model_name='projet',
            name='id',
            field=models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
    ),
    ]

Projet model is like that :

class Group(models.Model) :
    name = models.CharField(max_length=30, db_index=True)

    class Meta :
        abstract = True
        unique_together = (("id", "name"),)


class Projet(Group) :
    presentation = models.TextField(max_length=2500, null=True)

Realy I don't understand why I have this error... my settings configuration database is good, all others models work, ...

If I forgot something, please don't hesitate to tell me ! I need realy your helps !

Answer 1

Your model definition doesn't identify any of the fields as a primary key, therefore Django assumes a primary key column named id. However this column doesn't actually exist in the table.

Change your model definition to designate one of the fields as a primary key, and Django won't try to look for an id column.